Exciplex Emission in the POSS Possessing Two Kinds of Luminophores

Here we report the synthesis and luminescent properties of the modified polyhedral oligomeric silsesquioxane (POSS) that possesses two types of luminophores, cyanobenzene and N,N-diethylaniline for inducing significant emission not only from each dye but also from molecular interactions on the POSS core. From the optical measurements in the diluted solution, we observed both locally-excited emission and excimer emission originating from intramolecular interactions assisted by POSS. Moreover, highly-efficient exciplex emission was observed from the thin film, indicating that the interaction between luminophores easily occurs in the solid state by accumulating two kinds of molecules in the single POSS molecule. Finally, we also found that the modified POSS showed a unique acid responsiveness which can be caused by protonation at two types of amino moieties. In this manuscript, it is shown that POSS is able to play various roles at the same time: recruiting excited molecules to form exciplexes, suppressing concentration quenching in the solid state, and imparting stimulus responsiveness to exciplexes.